fix(ui): let DropdownMenu popup size to content

DropdownMenuContent had `w-(--anchor-width)` which locks the popup
width to the trigger. With icon-sm kebab triggers (~32px) the popup
was clamped by `min-w-32` to 128px, and longer items like
"Unresolve thread" / "标记为已解决" wrapped onto two lines.

Anchor-width matching is the right behavior for Select / Combobox
(both keep that class), but a generic kebab menu should size to its
own content. Drop the `w-(--anchor-width)` and keep `min-w-32` as the
floor.

Co-authored-by: multica-agent <github@multica.ai>

packages/ui/components/ui/dropdown-menu.tsx

@@ -51,7 +51,7 @@ function DropdownMenuContent({
             e.stopPropagation()
             onClick?.(e)
           }}
-          className={cn("z-50 max-h-(--available-height) w-(--anchor-width) min-w-32 origin-(--transform-origin) overflow-x-hidden overflow-y-auto rounded-lg bg-popover p-1 text-popover-foreground shadow-md ring-1 ring-foreground/10 duration-100 outline-none data-[side=bottom]:slide-in-from-top-2 data-[side=inline-end]:slide-in-from-left-2 data-[side=inline-start]:slide-in-from-right-2 data-[side=left]:slide-in-from-right-2 data-[side=right]:slide-in-from-left-2 data-[side=top]:slide-in-from-bottom-2 data-open:animate-in data-open:fade-in-0 data-open:zoom-in-95 data-closed:animate-out data-closed:overflow-hidden data-closed:fade-out-0 data-closed:zoom-out-95", className )}
+          className={cn("z-50 max-h-(--available-height) min-w-32 origin-(--transform-origin) overflow-x-hidden overflow-y-auto rounded-lg bg-popover p-1 text-popover-foreground shadow-md ring-1 ring-foreground/10 duration-100 outline-none data-[side=bottom]:slide-in-from-top-2 data-[side=inline-end]:slide-in-from-left-2 data-[side=inline-start]:slide-in-from-right-2 data-[side=left]:slide-in-from-right-2 data-[side=right]:slide-in-from-left-2 data-[side=top]:slide-in-from-bottom-2 data-open:animate-in data-open:fade-in-0 data-open:zoom-in-95 data-closed:animate-out data-closed:overflow-hidden data-closed:fade-out-0 data-closed:zoom-out-95", className )}
           {...props}
         />
       </MenuPrimitive.Positioner>